1. Field of the Invention
The present disclosure relates to the field of oil and gas exploration and production. More specifically, the present disclosure concerns a system and method for subterranean excavation using impactors. Yet more specifically, the present disclosure is directed to a system method of injecting impactors into a flow stream to form an impactor laden fluid stream for use in excavating a subterranean wellbore.
2. Description of Related Art
Boreholes for producing hydrocarbons within a subterranean are generally formed by a drilling system employing a rotating bit on the lower end of a drill string. The drill string is rotated by machinery on the Earth's surface. Drilling fluid is typically injected through the drill string that then exits the drill bit and travels back to the surface in the annulus between the drill string and wellbore inner circumference. The drilling fluid maintains downhole pressure in the wellbore to prevent hydrocarbons from migrating out of the formation and also washes away cuttings and other detritus resulting during drilling. The drilling bits are usually one of a roller cone bit or a fixed drag bit.
As described in the above referenced related applications, which are assigned to the assignee of the present application, impactors have recently been developed for use in subterranean excavations. Conventionally impactors are injected into a pressurized circulation fluid to form a combination. The combination is then directed to a drill string, having a bit on its lower end, and discharged through nozzles on the bit to structurally alter the subterranean formation. Because the impactors can damage the currently known means for pressurizing the circulation fluid, other methods are currently required for equalizing the pressure between the impactors and the circulation fluid for impactor injection.